Method of manufacturing polarizing plate

ABSTRACT

A method of manufacturing a polarizing plate according to an embodiment of the present invention includes: stretching and dyeing a laminate having a resin substrate and a polyvinyl alcohol-based resin layer formed on at least one side of the resin substrate to produce a polarizing film on the resin substrate; laminating an optically functional film on the laminate on a polarizing film side to produce an optically functional film laminate; and peeling the resin substrate from the optically functional film laminate. The peeling is performed so that an angle α formed between a surface of the optically functional film laminate immediately before the peeling and a peeling direction of the resin substrate is smaller than an angle β formed between the surface of the optically functional film laminate immediately before the peeling and a peeling direction of the polarizing film.

This application is a Divisional of U.S. application Ser. No.14/056,178, filed Oct. 17, 2015, which claims priority under 35 U.S.C.Section 119 to Japanese Patent Application Nos. 2012-251784 and2013-142375 each filed on Nov. 16, 2012, and Jul. 8, 2013, which areherein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of manufacturing a polarizingplate.

2. Description of the Related Art

Polarizing films are placed on both sides of a liquid crystal cell of aliquid crystal display apparatus as a typical image display apparatus,the placement being attributable to an image-forming mode of theapparatus. For example, the following method has been proposed as amethod of manufacturing the polarizing film (for example, JapanesePatent Application Laid-open No. 2000-338329). A laminate having a resinsubstrate and a polyvinyl alcohol (PVA)-based resin layer is stretched,and is then subjected to a dyeing treatment so that the polarizing filmmay be formed on the resin substrate. According to such method, apolarizing film having a small thickness is formed. Accordingly, themethod has been attracting attention because of its potential tocontribute to thinning of an image display apparatus in recent years.

By the way, the polarizing film is typically laminated on anotheroptically functional film (e.g., a protective film) and is used as apolarizing plate. However, the polarizing plate using the polarizingfilm produced by using the resin substrate involves the followingproblem. A wrinkle, foreign matter, or the like is liable to occur, andhence the polarizing plate is poor in external appearance.

SUMMARY OF THE INVENTION

According to an embodiment of the present invention, there is provided amethod of manufacturing a polarizing plate excellent in externalappearance.

A method of manufacturing a polarizing plate according to an embodimentof the present invention includes: stretching and dyeing a laminatehaving a resin substrate and a polyvinyl alcohol-based resin layerformed on one side of the resin substrate to produce a polarizing filmon the resin substrate; laminating an optically functional film on thelaminate on a polarizing film side to produce an optically functionalfilm laminate; and peeling the resin substrate from the opticallyfunctional film laminate. The peeling is performed so that an angle αformed between a surface of the optically functional film laminateimmediately before the peeling and a peeling direction of the resinsubstrate is smaller than an angle β formed between the surface of theoptically functional film laminate immediately before the peeling and apeeling direction of the polarizing film.

In one embodiment of the present invention, a difference between theangle α and the angle β is 60° or more. In one embodiment of the presentinvention, the difference between the angle α and the angle β is 90° to180°.

In one embodiment of the present invention, a tension needed for thepeeling is 3.0 N/15 mm or less.

In one embodiment of the present invention, the resin substrate has amodulus of elasticity at a time of the peeling of 2 GPa to 3 GPa.

In one embodiment of the present invention, the resin substrate has aradius of curvature at a time of the peeling of 1 mm to 10 mm.

In one embodiment of the present invention, in the peeling, a peelingroll is arranged on the optically functional film laminate on anoptically functional film side, and the peeling is performed with an aidof the peeling roll. In one embodiment of the present invention, thepeeling roll has a diameter of 10 mm to 30 mm.

In one embodiment of the present invention, in the peeling, a peelingbar is arranged on the optically functional film laminate on anoptically functional film side, and the peeling is performed with an aidof the peeling bar. In one embodiment of the present invention, thepeeling bar has a diameter of a tip portion of 5 mm to 30 mm.

In one embodiment of the present invention, a surface of the opticallyfunctional film laminate on the optically functional film side has asurface protective film attached thereto.

According to another aspect of the present invention, a polarizing plateis provided. The polarizing plate is obtained by the manufacturingmethod as described above.

According to an embodiment of the present invention, an opticallyfunctional film is laminated on a polarizing film formed on a resinsubstrate to produce an optically functional film laminate, and uponpeeling of the resin substrate from the optically functional filmlaminate, an angle α formed between the surface of the opticallyfunctional film laminate immediately before the peeling and the peelingdirection of the resin substrate is set to be smaller than an angle βformed between the surface of the optically functional film laminateimmediately before the peeling and the peeling direction of thepolarizing film, whereby the resin substrate can be satisfactorilypeeled while the occurrence of a wrinkle, foreign matter (such as asubstrate residue), or the like is suppressed. As a result, a polarizingplate extremely excellent in external appearance can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a partial sectional view of a laminate according to anembodiment of the present invention;

FIG. 2 is an explanatory diagram of a method of measuring a radius ofcurvature R;

FIG. 3 is a schematic view illustrating an example of a peeling step inthe present invention;

FIG. 4 is a schematic view illustrating another example of the peelingstep in the present invention;

FIG. 5A is a schematic view illustrating still another example of thepeeling step in the present invention; and

FIG. 5B is a schematic view illustrating still another example of thepeeling step in the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of the present invention are described.However, the present invention is not limited to these embodiments.

A method of manufacturing a polarizing plate according to an embodimentof the present invention includes: stretching and dyeing a laminatehaving a resin substrate and a polyvinyl alcohol-based resin layerformed on one side of the resin substrate to produce a polarizing filmon the resin substrate; laminating an optically functional film on apolarizing film side of the laminate to produce an optically functionalfilm laminate; and peeling the resin substrate from the opticallyfunctional film laminate. Hereinafter, the respective steps aredescribed.

A. Step of Producing Polarizing Film A-1. Laminate

FIG. 1 is a partial sectional view of a laminate according to anembodiment of the present invention. A laminate 10 has a resin substrate11 and a polyvinyl alcohol-based resin layer 12. The laminate 10 isproduced by forming the polyvinyl alcohol-based resin layer 12 on theresin substrate 11 having a long shape. Any appropriate method may beadopted as a method of forming the polyvinyl alcohol-based resin layer12. The polyvinyl alcohol-based resin (hereinafter referred to as“PVA-based resin”) layer 12 is preferably formed by applying anapplication liquid containing a PVA-based resin onto the resin substrate11 and drying the liquid.

As a formation material for the resin substrate, any appropriatethermoplastic resin may be adopted. Examples of the thermoplastic resininclude: an ester-based resin such as a polyethylene terephthalate-basedresin; a cycloolefin-based resin such as a norbornene-based resin; anolefin-based resin such as polypropylene; a polyamide-based resin; apolycarbonate-based resin; and a copolymer resin thereof. Of those, anorbornene-based resin and an amorphous polyethylene terephthalate-basedresin are preferred.

In one embodiment, an amorphous (uncrystallized) polyethyleneterephthalate-based resin is preferably used. In particular, anoncrystalline (hard-to-crystallize) polyethylene terephthalate-basedresin is particularly preferably used. Specific examples of thenoncrystalline polyethylene terephthalate-based resin include acopolymer further containing isophthalic acid as a dicarboxylic acidcomponent and a copolymer further containing cyclohexane dimethanol as aglycol component.

When an underwater stretching mode is adopted in a stretching treatmentto be described later, the resin substrate can absorb water and thewater acts as like a plasticizer so that the substrate can plasticize.As a result, a stretching stress can be significantly reduced.Accordingly, the stretching can be performed at a high ratio and thestretchability of the resin substrate can be more excellent than that atthe time of in-air stretching. As a result, a polarizing film havingexcellent optical characteristics can be produced. In one embodiment,the percentage of water absorption of the resin substrate is preferably0.2% or more, more preferably 0.3% or more. Meanwhile, the percentage ofwater absorption of the resin substrate is preferably 3.0% or less, morepreferably 1.0% or less. The use of such resin substrate can prevent,for example, the following inconvenience: the dimensional stability ofthe resin substrate remarkably reduces at the time of the production andhence the external appearance of the polarizing film to be obtaineddeteriorates. In addition, the use of such resin substrate can preventthe rupture of the substrate at the time of the underwater stretchingand the peeling of the PVA-based resin layer from the resin substrate.It should be noted that the percentage of water absorption of the resinsubstrate can be adjusted by, for example, introducing a modificationgroup into the constituent material. The percentage of water absorptionis a value determined in conformity with JIS K 7209.

The glass transition temperature (Tg) of the resin substrate ispreferably 170° C. or less. The use of such resin substrate cansufficiently secure the stretchability of the laminate while suppressingthe crystallization of the PVA-based resin layer. Further, the glasstransition temperature is more preferably 120° C. or less inconsideration of the plasticization of the resin substrate by water andfavorable performance of the underwater stretching. In one embodiment,the glass transition temperature of the resin substrate is preferably60° C. or more. The use of such resin substrate prevents aninconvenience such as the deformation of the resin substrate (e.g., theoccurrence of unevenness, a slack, or a wrinkle) during the applicationand drying of the application liquid containing the PVA-based resin,thereby enabling favorable production of the laminate. In addition, theuse enables favorable stretching of the PVA-based resin layer at asuitable temperature (e.g., about 60° C.). In another embodiment, aglass transition temperature of less than 60° C. is permitted as long asthe resin substrate does not deform during the application and drying ofthe application liquid containing the PVA-based resin. It should benoted that the glass transition temperature of the resin substrate canbe adjusted by, for example, introducing a modification group into theformation material or heating the substrate constituted of acrystallization material. The glass transition temperature (Tg) is avalue determined in conformity with JIS K 7121.

The thickness of the resin substrate before the stretching is preferably20 μm to 300 μm, more preferably 50 μm to 200 μm. When the thickness isless than 20 μm, it may be difficult to form the PVA-based resin layer.When the thickness exceeds 300 μm, in, for example, underwaterstretching, it may take a long time for the resin substrate to absorbwater, and an excessively large load may be needed in the stretching.

Any appropriate resin may be adopted as the PVA-based resin for formingthe PVA-based resin layer. Examples of the resin include polyvinylalcohol and an ethylene-vinyl alcohol copolymer. The polyvinyl alcoholis obtained by saponifying polyvinyl acetate. The ethylene-vinyl alcoholcopolymer is obtained by saponifying an ethylene-vinyl acetatecopolymer. The saponification degree of the PVA-based resin is typically85 mol % to 100 mol %, preferably 95.0 mol % to 99.95 mol %, morepreferably 99.0 mol % to 99.93 mol %. The saponification degree can bedetermined in conformity with JIS K 6726-1994. The use of the PVA-basedresin having such saponification degree can provide a polarizing filmexcellent in durability. When the saponification degree is excessivelyhigh, the resin may gel.

The average polymerization degree of the PVA-based resin may beappropriately selected depending on purposes. The average polymerizationdegree is typically 1,000 to 10,000, preferably 1,200 to 5,000, morepreferably 1,500 to 4,500. It should be noted that the averagepolymerization degree can be determined in conformity with JIS K6726-1994.

The application liquid is typically a solution prepared by dissolvingthe PVA-based resin in a solvent. Examples of the solvent include water,dimethylsulfoxide, dimethylformamide, dimethylacetamide,N-methylpyrrolidone, various glycols, polyhydric alcohols such astrimethylolpropane, and amines such as ethylenediamine anddiethylenetriamine. They may be used alone or in combination. Of those,water is preferred. The concentration of the PVA-based resin of thesolution is preferably 3 parts by weight to 20 parts by weight withrespect to 100 parts by weight of the solvent. At such resinconcentration, a uniform coating film in close contact with the resinsubstrate can be formed.

The application liquid may be compounded with an additive. Examples ofthe additive include a plasticizer and a surfactant. Examples of theplasticizer include polyhydric alcohols such as ethylene glycol andglycerin. Examples of the surfactant include nonionic surfactants. Suchadditive can be used for the purpose of additionally improving theuniformity, dyeing property, or stretchability of the PVA-based resinlayer to be obtained. In addition, examples of the additive include aneasy-adhesion component. The use of the easy-adhesion component canimprove adhesiveness between the resin substrate and the PVA-based resinlayer. As a result, an inconvenience such as peeling of the PVA-basedresin layer from the substrate is suppressed, and dyeing and underwaterstretching to be described later can be satisfactorily performed.

Examples of the easy-adhesion component include a modified PVA such asacetoacetyl modified PVA. A polymer having at least a repeating unitrepresented by the below-indicated general formula (I) is preferablyused as the acetoacetyl modified PVA.

In the formula (I), the ratio of “n” to “l+m+n” (modification degree) ispreferably 1% to 10%.

The saponification degree of the acetoacetyl modified PVA is preferably97 mol % or more. In addition, the pH of a 4-wt % aqueous solution ofthe acetoacetyl modified PVA is preferably 3.5 to 5.5.

The modified PVA is added so that the amount of the modified PVA ispreferably 3 wt % or more, more preferably 5 wt % or more with respectto the total weight of the PVA-based resins in the application liquid.On the other hand, the amount of the modified PVA added is preferably 30wt % or less.

Any appropriate method may be adopted as a method of applying theapplication liquid. Examples of the method include a roll coatingmethod, a spin coating method, a wire bar coating method, a dip coatingmethod, a die coating method, a curtain coating method, a spray coatingmethod, and a knife coating method (comma coating method or the like).

The application liquid is preferably applied and dried at a temperatureof 50° C. or more.

The thickness of the PVA-based resin layer before the stretching ispreferably 3 μm to 40 μm, more preferably 5 μm to 20 μm.

The resin substrate may be subjected to a surface treatment (such as acorona treatment) before the formation of the PVA-based resin layer.Alternatively, an easy-adhesion layer may be formed on the resinsubstrate. Of those, the formation of an easy-adhesion layer (a coatingtreatment) is preferably performed. For example, an acrylic resin or apolyvinyl alcohol-based resin is used as a material for forming theeasy-adhesion layer. Of those, a polyvinyl alcohol-based resin isparticularly preferred. Examples of the polyvinyl alcohol-based resininclude a polyvinyl alcohol resin and a modified product thereof.Examples of the modified product of the polyvinyl alcohol resin includethe acetoacetyl modified PVA. It should be noted that the thickness ofthe easy-adhesion layer is preferably about 0.05 μm to 1 μm. Suchtreatment can improve adhesiveness between the resin substrate and thePVA-based resin layer. As a result, for example, an inconvenience suchas peeling of the PVA-based resin layer from the substrate issuppressed, and dyeing and underwater stretching to be described latercan be satisfactorily performed.

A-2. Stretching of Laminate

Any appropriate method may be adopted as a method of stretching thelaminate. Specifically, fixed-end stretching may be adopted or free-endstretching (such as a method involving passing the laminate throughrolls having different peripheral speeds to uniaxially stretch thelaminate) maybe adopted. Of those, free-end stretching is preferred.

The stretching direction of the laminate maybe appropriately set. In oneembodiment, the laminate having a long shape is stretched in itslengthwise direction. In this case, there may be typically adopted amethod involving passing the laminate between rolls having differentperipheral speeds to stretch the laminate. In another embodiment, thelaminate having a long shape is stretched in its widthwise direction. Inthis case, there may be typically adopted a method involving stretchingthe laminate using a tenter stretching apparatus.

A stretching mode is not particularly limited and may be an in-airstretching mode or an underwater stretching mode. Of those, anunderwater stretching mode is preferred. According to the underwaterstretching mode, the stretching can be performed at a temperature lowerthan the glass transition temperature (typically about 80° C.) of eachof the resin substrate and the PVA-based resin layer, and hence thePVA-based resin layer can be stretched at a high ratio while itscrystallization is suppressed. As a result, a polarizing film havingexcellent optical characteristics can be produced.

The stretching of the laminate maybe performed in one stage, or may beperformed in a plurality of stages. When the stretching is performed ina plurality of stages, for example, the free-end stretching and thefix-end stretching may be performed in combination, or the underwaterstretching mode and the in-air stretching mode maybe performed incombination. When the stretching is performed in a plurality of stages,the stretching ratio (maximum stretching ratio) of the laminate to bedescribed later is the product of stretching ratios in the respectivestages.

The stretching temperature of the laminate may be set to any appropriatevalue depending on, for example, a formation material for the resinsubstrate and the stretching mode. When the in-air stretching mode isadopted, the stretching temperature is preferably equal to or higherthan the glass transition temperature (Tg) of the resin substrate, morepreferably Tg+10° C. or more, particularly preferably Tg+15° C. or more.Meanwhile, the stretching temperature of the laminate is preferably 170°C. or less. Performing the stretching at such temperature suppressesrapid progress of the crystallization of the PVA-based resin, therebyenabling the suppression of an inconvenience due to the crystallization(such as the inhibition of the orientation of the PVA-based resin layerby the stretching).

When the underwater stretching mode is adopted as a stretching mode, theliquid temperature of a stretching bath is preferably 40° C. to 85° C.,more preferably 50° C. to 85° C. At such temperature, the PVA-basedresin layer can be stretched at a high ratio while its dissolution issuppressed. Specifically, as described above, the glass transitiontemperature (Tg) of the resin substrate is preferably 60° C. or more inrelation to the formation of the PVA-based resin layer. In this case,when the stretching temperature falls short of 40° C., there is apossibility that the stretching cannot be satisfactorily performed evenin consideration of the plasticization of the resin substrate by water.On the other hand, as the temperature of the stretching bath increases,the solubility of the PVA-based resin layer is raised and henceexcellent optical characteristics may not be obtained. The laminate ispreferably immersed in the stretching bath for a time of 15 seconds to 5minutes.

When the underwater stretching mode is adopted, the laminate ispreferably stretched while being immersed in an aqueous solution ofboric acid (in-boric-acid-solution stretching). The use of the aqueoussolution of boric acid as the stretching bath can impart, to thePVA-based resin layer, rigidity enough to withstand a tension to beapplied at the time of the stretching and such water resistance that thelayer does not dissolve in water. Specifically, boric acid can produce atetrahydroxyborate anion in the aqueous solution to cross-link with thePVA-based resin through a hydrogen bond. As a result, the PVA-basedresin layer can be satisfactorily stretched with the aid of the rigidityand the water resistance imparted thereto, and hence a polarizing filmhaving excellent optical characteristics can be produced.

The aqueous solution of boric acid is preferably obtained by dissolvingboric acid and/or a borate in water as a solvent. The concentration ofboric acid is preferably 1 part by weight to 10 parts by weight withrespect to 100 parts by weight of water. Setting the concentration ofboric acid to 1 part by weight or more can effectively suppress thedissolution of the PVA-based resin layer, thereby enabling theproduction of a polarizing film having additionally highcharacteristics. It should be noted that an aqueous solution obtained bydissolving a boron compound such as borax, glyoxal, glutaric aldehyde,or the like as well as boric acid or the borate in the solvent may alsobe used.

When the PVA-based resin layer has been caused to adsorb a dichromaticsubstance (typically iodine) in advance by dyeing to be described later,the stretching bath (aqueous solution of boric acid) is preferablycompounded with an iodide. Compounding the bath with the iodide cansuppress the elution of iodine that the PVA-based resin layer has beencaused to adsorb. Examples of the iodide include potassium iodide,lithium iodide, sodium iodide, zinc iodide, aluminum iodide, leadiodide, copper iodide, barium iodide, calcium iodide, tin iodide, andtitanium iodide. Of those, potassium iodide is preferred. Theconcentration of the iodide is preferably 0.05 part by weight to 15parts by weight, more preferably 0.5 part by weight to 8 parts by weightwith respect to 100 parts by weight of water.

The stretching ratio (maximum stretching ratio) of the laminate ispreferably 5.0 times or more with respect to the original length of thelaminate. Such high stretching ratio can be achieved by adopting, forexample, the underwater stretching mode (in-boric-acid-solutionstretching). It should be noted that the term “maximum stretching ratio”as used in this specification refers to a stretching ratio immediatelybefore the rupture of the laminate. The stretching ratio at which thelaminate ruptures is separately identified and a value lower than thevalue by 0.2 is the maximum stretching ratio.

In one embodiment, the laminate is subjected to in-air stretching athigh temperature (e.g., 95° C. or more), and then subjected to thein-boric-acid-solution stretching, and dyeing to be described later.Such in-air stretching is hereinafter referred to as “preliminary in-airstretching” because the stretching can be ranked as stretchingpreliminary or auxiliary to the in-boric-acid-solution stretching.

When the preliminary in-air stretching is combined with thein-boric-acid-solution stretching, the laminate can be stretched at anadditionally high ratio in some cases. As a result, a polarizing filmhaving additionally excellent optical characteristics (such as apolarization degree) can be produced. For example, when a polyethyleneterephthalate-based resin is used as the resin substrate, the resinsubstrate can be stretched satisfactorily, while its orientation issuppressed, by a combination of the preliminary in-air stretching andthe in-boric-acid-solution stretching than that in the case of thein-boric-acid-solution stretching alone. As the orientation property ofthe resin substrate is raised, its stretching tension increases andhence it becomes difficult to stably stretch the substrate or the resinsubstrate ruptures. Accordingly, the laminate can be stretched at anadditionally high ratio by stretching the resin substrate whilesuppressing its orientation.

In addition, when the preliminary in-air stretching is combined with thein-boric-acid-solution stretching, the orientation property of thePVA-based resin is improved and hence the orientation property of thePVA-based resin can be improved even after the in-boric-acid-solutionstretching. Specifically, the orientation property of the PVA-basedresin is improved in advance by the preliminary in-air stretching sothat the PVA-based resin may easily cross-link with boric acid duringthe in-boric-acid-solution stretching. Then, the stretching is performedin a state where boric acid serves as a junction, and hence theorientation property of the PVA-based resin is assumed to be high evenafter the in-boric-acid-solution stretching. As a result, a polarizingfilm having excellent optical characteristics (such as a polarizationdegree) can be produced.

The stretching ratio in the preliminary in-air stretching is preferably3.5 times or less. A stretching temperature in the preliminary in-airstretching is preferably equal to or higher than the glass transitiontemperature of the PVA-based resin. The stretching temperature ispreferably 95° C. to 150° C. It should be noted that the maximumstretching ratio when the preliminary in-air stretching and thein-boric-acid-solution stretching are combined with each other ispreferably 5.0 times or more, more preferably 5.5 times or more, stillmore preferably 6.0 times or more with respect to the original length ofthe laminate.

A-3. Dyeing

The dyeing of the laminate is typically performed by causing thePVA-based resin layer to adsorb a dichromatic substance (preferablyiodine). A method for the adsorption is, for example, a method involvingimmersing the PVA-based resin layer (laminate) in a dyeing liquidcontaining iodine, a method involving applying the dyeing liquid to thePVA-based resin layer, or a method involving spraying the dyeing liquidon the PVA-based resin layer. Of those, a method involving immersing thelaminate in the dyeing liquid is preferred. This is because iodine cansatisfactorily adsorb to the layer.

The dyeing liquid is preferably an aqueous solution of iodine. Thecompounding amount of iodine is preferably 0.1 part by weight to 0.5part by weight with respect to 100 parts by weight of water. The aqueoussolution of iodine is preferably compounded with an iodide so that thesolubility of iodine in water may be increased. Specific examples of theiodide are as described above. The compounding amount of the iodide ispreferably 0.02 part by weight to 20 parts by weight, more preferably0.1 part by weight to 10 parts by weight with respect to 100 parts byweight of water. The liquid temperature of the dyeing liquid at the timeof the dyeing is preferably 20° C. to 50° C. so that the dissolution ofthe PVA-based resin may be suppressed. When the PVA-based resin layer isimmersed in the dyeing liquid, an immersion time is preferably 5 secondsto 5 minutes so that the transmittance of the PVA-based resin layer maybe secured. In addition, the dyeing conditions (the concentration, theliquid temperature, and the immersion time) can be set so that thepolarization degree or single axis transmittance of the polarizing filmto be finally obtained may fall within a predetermined range. In oneembodiment, the immersion time is set so that the polarization degree ofthe polarizing film to be obtained may be 99.98% or more. In anotherembodiment, the immersion time is set so that the single axistransmittance of the polarizing film to be obtained may be 40% to 44%.

The dyeing treatment can be performed at any appropriate timing. Whenthe underwater stretching is performed, the dyeing treatment ispreferably performed before the underwater stretching.

A-4. Any Other Treatment

The laminate may be appropriately subjected to a treatment for formingthe PVA-based resin layer into a polarizing film in addition to thestretching and dyeing. Examples of the treatment for forming thePVA-based resin layer into the polarizing film include an insolubilizingtreatment, a cross-linking treatment, a washing treatment, and a dryingtreatment. It should be noted that the number of times, order, and thelike of these treatments are not particularly limited.

The insolubilizing treatment is typically performed by immersing thePVA-based resin layer in an aqueous solution of boric acid. Waterresistance can be imparted to the PVA-based resin layer by subjectingthe layer to the insolubilizing treatment. The concentration of theaqueous solution of boric acid is preferably 1 part by weight to 4 partsby weight with respect to 100 parts by weight of water. The liquidtemperature of an insolubilizing bath (the aqueous solution of boricacid) is preferably 20° C. to 50° C. The insolubilizing treatment ispreferably performed before the underwater stretching treatment or thedyeing treatment.

The cross-linking treatment is typically performed by immersing thePVA-based resin layer in an aqueous solution of boric acid. Waterresistance can be imparted to the PVA-based resin layer by subjectingthe layer to the cross-linking treatment. The concentration of theaqueous solution of boric acid is preferably 1 part by weight to 5 partsby weight with respect to 100 parts by weight of water. In addition,when the cross-linking treatment is performed after the dyeingtreatment, the solution is preferably further compounded with an iodide.Compounding the solution with the iodide can suppress the elution ofiodine which the PVA-based resin layer has been caused to adsorb. Thecompounding amount of the iodide is preferably 1 part by weight to 5parts by weight with respect to 100 parts by weight of water. Specificexamples of the iodide are as described above. The liquid temperature ofa cross-linking bath (the aqueous solution of boric acid) is preferably20° C. to 60° C. The cross-linking treatment is preferably performedbefore the underwater stretching treatment. In a preferred embodiment,the dyeing treatment, the cross-linking treatment, and the underwaterstretching treatment are performed in the stated order.

The washing treatment is typically performed by immersing the PVA-basedresin layer in an aqueous solution of potassium iodide. The dryingtemperature in the drying treatment is preferably 30° C. to 100° C.

A-5. Polarizing Film

The polarizing film is substantially a PVA-based resin layer thatadsorbs and orients a dichromatic substance. The thickness of thepolarizing film is typically 25 μm or less, preferably 15 μm or less,more preferably 10 μm or less, still more preferably 7 μm or less,particularly preferably 5 μm or less. Meanwhile, the thickness of thepolarizing film is preferably 0.5 μm or more, more preferably 1.5 μm ormore. The polarizing film preferably shows absorption dichroism at anywavelength in the wavelength range of 380 nm to 780 nm. The single axistransmittance of the polarizing film is preferably 40.0% or more, morepreferably 41.0% or more, still more preferably 42.0% or more,particularly preferably 43.0% or more. The polarization degree of thepolarizing film is preferably 99.8% or more, more preferably 99.9% ormore, still more preferably 99.95% or more.

B. Step of Producing Optically Functional Film Laminate

After the laminate (PVA-based resin layer) has been subjected to therespective treatments, an optically functional film is laminated on thelaminate on the polarizing film (PVA-based resin layer) side. Anoptically functional film having a long shape is typically laminated onthe laminate having a long shape so that their lengthwise directions arealigned.

The optically functional film can function as, for example, a protectivefilm for a polarizing film or a retardation film.

Any appropriate resin film may be adopted as the optically functionalfilm. As a formation material for the optically functional film, thereare given, for example: a cellulose-based resin such as triacetylcellulose (TAC); a cycloolefin-based resin such as a norbornene-basedresin; an olefin-based resin such as polyethylene or polypropylene; apolyester-based resin; and a (meth)acrylic resin. It should be notedthat the term “(meth)acrylic resin” refers to an acrylic resin and/or amethacrylic resin.

The thickness of the optically functional film is typically 10 μm to 100μm, preferably 20 μm to 60 μm. It should be noted that the opticallyfunctional film may be subjected to various surface treatments.

The modulus of elasticity of the optically functional film is preferably2 GPa or more, more preferably 2 GPa to 6 GPa. When one end portion ofan optically functional film 20 is held in a state where the other endportion thereof is bonded to a substrate 110, and is then bent in a 180°direction with respect to the bonding surface as illustrated in FIG. 2,a radius of curvature R of the bent portion is preferably 3 mm or more,more preferably 5 mm or more. A peeling step to be described later canbe performed more satisfactorily by using such optically functionalfilm.

The lamination of the optically functional film is performed using anyappropriate adhesive or pressure-sensitive adhesive. In one embodiment,the adhesive is applied onto the surface of the polarizing film beforethe optically functional film is attached. The adhesive may be anaqueous adhesive, or may be a solvent-based adhesive. Of those, anaqueous adhesive is preferably used.

Any appropriate aqueous adhesive may be adopted as the aqueous adhesive.An aqueous adhesive containing a PVA-based resin is preferably used. Theaverage polymerization degree of the PVA-based resin in the aqueousadhesive is preferably about 100 to 5,000, more preferably 1,000 to4,000 in terms of adhesion. Its average saponification degree ispreferably about 85 mol % to 100 mol %, more preferably 90 mol % to 100mol % in terms of adhesion.

The PVA-based resin in the aqueous adhesive preferably contains anacetoacetyl group. This is because such resin can be excellent inadhesiveness between the PVA-based resin layer and the opticallyfunctional film, and in durability. The acetoacetyl group-containingPVA-based resin is obtained by, for example, causing a PVA-based resinand diketene to react with each other by any appropriate method. Theacetoacetyl group modification degree of the acetoacetylgroup-containing PVA-based resin is typically 0.1 mol % or more,preferably about 0.1 mol % to 40 mol %, more preferably 1 mol % to 20mol %, particularly preferably 2 mol % to 7 mol %. It should be notedthat the acetoacetyl group modification degree is a value measured byNMR.

The resin concentration of the aqueous adhesive is preferably 0.1 wt %to 15 wt %, more preferably 0.5 wt % to 10 wt %.

The thickness of the adhesive at the time of the application can be setto any appropriate value. For example, the thickness is set so that anadhesive layer having a desired thickness may be obtained after heating(drying). The thickness of the adhesive layer is preferably 10 nm to 300nm, more preferably 10 nm to 200 nm, particularly preferably 20 nm to150 nm.

Heating is preferably performed after lamination of the opticallyfunctional film. A temperature for the heating is preferably 50° C. ormore, more preferably 55° C. or more, still more preferably 60° C. ormore, particularly preferably 80° C. or more. It should be noted thatthe heating performed after lamination of the optically functional filmmay also serve as the drying treatment of the laminate. In addition, theheating may be performed before or after a peeling step to be describedlater, and is preferably performed before the peeling step.

C. Peeling Step

The resin substrate is peeled from the optically functional filmlaminate. At that time, the peeling is performed so that an angle αformed between the surface of the optically functional film laminateimmediately before the peeling and the peeling direction of the resinsubstrate maybe smaller than an angle β formed between the surface ofthe optically functional film laminate immediately before the peelingand the peeling direction of the polarizing film. According to suchembodiment, the resin substrate can be satisfactorily peeled while theoccurrence of a wrinkle, foreign matter (such as a substrate residue),or the like is suppressed. As a result, a polarizing plate extremelyexcellent in external appearance can be obtained. In addition, a tensionneeded for the peeling can be reduced and hence a load on facilities canbe alleviated.

A difference between the angle β and the angle α is preferably 60° ormore, more preferably 90° to 180°. The angle α is preferably 30° orless, more preferably 0° to 20°. The angle β is preferably 60° or more,more preferably 90° to 180°.

A tension (peel tension) needed for the peeling is preferably 3.0 N/15mm or less, more preferably 1.0 N/15 mm or less, particularly preferably0.5 N/15 mm or less.

FIG. 3 is a schematic view illustrating an example of the peeling step.An optically functional film laminate 100 has the resin substrate 11, apolarizing film 12′, and the optically functional film 20 in the statedorder. In the illustrated example, the resin substrate 11 is peeled fromthe optically functional film laminate 100 by pulling, while conveyingthe optically functional film laminate 100 in a substantially horizontaldirection, a laminate (polarizing plate) 50 of the polarizing film 12′and the optically functional film 20 upward with respect to theconveyance surface of the optically functional film laminate 100. At thetime of the peeling, the peeling direction of the resin substrate 11 issubstantially the same as the conveyance direction of the opticallyfunctional film laminate 100 immediately before the peeling, and thepeeling direction of the polarizing film 12′ is the pulling direction.Therefore, in the illustrated example, the angle α is substantially 0°.

FIG. 4 is a schematic view illustrating another example of the peelingstep. In this illustrated example, the resin substrate 11 is peeled fromthe optically functional film laminate 100 by pulling, while conveyingthe optically functional film laminate 100 so that its resin substrate11 side may be brought into contact with a roll 120, the laminate(polarizing plate) 50 of the polarizing film 12′ and the opticallyfunctional film 20 in a direction going away from the roll 120 withrespect to the conveyance surface of the optically functional filmlaminate 100. In this example, the surface of the optically functionalfilm laminate immediately before the peeling is a surface including atangent at the point at which the polarizing film 12′ goes away. At thetime of the peeling, the peeling direction of the resin substrate 11 issubstantially the same as the conveyance direction of the opticallyfunctional film laminate 100 immediately before the peeling, and thepeeling direction of the polarizing film 12′ is the pulling direction.Therefore, in the illustrated example, such angle α as illustrated inFIG. 4 is specified and the angle α is smaller than the angle β.

The modulus of elasticity of the resin substrate at the time of thepeeling is typically 2 GPa to 3 GPa. The modulus of elasticity of theresin substrate before the stretching is typically 2 GPa to 3 GPa. Themodulus of elasticity of the laminate (polarizing plate) of thepolarizing film and the optically functional film is preferably 4 GPa to7 GPa. In addition, the radius of curvature R of the resin substrate (atthe time of the peeling) is typically 1 mm to 10 mm. The radius ofcurvature R of the laminate (polarizing plate) of the polarizing filmand the optically functional film is preferably 3 mm to 30 mm. When thePVA-based resin layer is subjected to a treatment such as stretching orcross-linking, the rigidity of the polarizing film to be obtained ishigh and hence the film can sufficiently resist such peeling asdescribed above.

In the peeling step, peeling auxiliary means may be placed on theoptically functional film laminate 100 on the optically functional film20 side so that the peeling may be performed more easily, moresatisfactorily, and more stably. Examples of the peeling auxiliary meansinclude such peeling roll 70 as illustrated in FIG. 5A and such peelingbar 80 as illustrated in FIG. 5B. The peeling roll 70 is brought intoabutment with the optically functional film laminate 100 on theoptically functional film 20 side and the roll itself aids the peelingwhile rotating. When the peeling roll is used, a roll diameter ispreferably 5 mm to 80 mm, more preferably 5 mm to 50 mm, still morepreferably 10 mm to 30 mm. When the roll diameter is excessively large,a peel strength becomes large and hence good peeling cannot be performedin some cases. When the roll diameter is excessively small, the strengthof the roll becomes insufficient and hence peeling stability becomesinsufficient in some cases. When the peeling bar 80 is used, the peelingbar typically has a tip portion whose section is of a semicircularshape, the tip portion is brought into abutment with the opticallyfunctional film laminate 100 on the optically functional film 20 side,and the bar aids the peeling without rotating. When the peeling bar isused, the diameter of the tip portion is preferably 5 mm to 80 mm, morepreferably 5 mm to 50 mm, still more preferably 5 mm to 30 mm. At thistime, a surface protective film may be laminated on a surface of theoptically functional film laminate on the optically functional film sidefor preventing the occurrence of a flaw due to the peeling roll or thepeeling bar. Although the surface protective film is not particularlylimited, the surface protective film is typically, for example, apolyethylene-based film having a pressure-sensitive adhesive layerprovided on its surface, and the film can be attached to the surface ofthe optically functional film with the pressure-sensitive adhesivelayer.

EXAMPLES

Hereinafter, the present invention is specifically described byway ofExamples. However, the present invention is not limited to Examplesshown below. It should be noted that methods of measuring the respectivecharacteristics are as described below.

1. Thickness

Measurement was performed with a digital micrometer (manufactured byANRITSU CORPORATION, product name: “KC-351C”).

2. Glass Transition Temperature (Tg)

Measurement was performed in conformity with JIS K 7121.

3. Modulus of Elasticity

A sample was formed into a tensile test dumbbell whose parallel portionhad a width of 10 mm and a length of 40 mm on the basis of JISK6734:2000, and then its modulus of elasticity in tension was determinedby performing a tensile test in conformity with JIS K7161:1994.

4. Radius of Curvature R

As illustrated in FIG. 2, one end portion in the lengthwise direction ofa test piece having a width of 50 mm was held in a state where the otherend portion thereof was bonded to a substrate, and was then bent bybeing pulled in a 180° direction with respect to the bonding surfacewith a force of 150 gw. A radius of curvature was determined bymeasuring the radius of the bent portion at that time. It should benoted that the test piece was cut out so that its lengthwise directioncorresponded to a peeling direction.

5. Peel Tension

One end portion in the lengthwise direction of a test piece (opticallyfunctional film laminate) having a width of 15 mm and a length of 100 mmwas peeled in advance, and then the peeled portion was held and peeledin a specified angle direction at a rate of 3 m/min. A peel tension wasdetermined by measuring a tension at the time of the peeling.

Example 1-1

An amorphous polyethylene terephthalate (A-PET) film (manufactured byMitsubishi Chemical Corporation, trade name: “NOVACLEAR,” thickness: 100μm) having a long shape and having a percentage of water absorption of0.60%, a Tg of 80° C., and a modulus of elasticity of 2.5 GPa was usedas a resin substrate.

One surface of the resin substrate was subjected to a corona treatment(treatment condition: 55 W·mim/m²), and an aqueous solution containing90 parts by weight of polyvinyl alcohol (polymerization degree: 4,200,saponification degree: 99.2 mol %) and 10 parts by weight ofacetoacetyl-modified PVA (polymerization degree: 1,200, acetoacetylmodification degree: 4.6%, saponification degree: 99.0 mol % or more,manufactured by The Nippon Synthetic Chemical Industry Co., Ltd., tradename: “GOHSEFIMER Z200”) was applied onto the surface subjected to thecorona treatment, and was then dried at 60° C. so that a PVA-based resinlayer having a thickness of 10 μm was formed, thereby producing alaminate.

The resultant laminate was subjected to free-end uniaxial stretching inits longitudinal direction (lengthwise direction) at 1.8 times in anoven at 120° C. between rolls having different peripheral speeds(preliminary in-air stretching).

Next, the laminate was immersed in an insolubilizing bath having aliquid temperature of 30° C. (an aqueous solution of boric acid obtainedby compounding 100 parts by weight of water with 4 parts by weight ofboric acid) for 30 seconds (insolubilizing treatment).

Next, the laminate was immersed in a dyeing bath having a liquidtemperature of 30° C. (an aqueous solution of iodine obtained bycompounding 100 parts by weight of water with 0.2 part by weight ofiodine and 1.0 part by weight of potassium iodide) for 60 seconds(dyeing treatment).

Next, the laminate was immersed in a cross-linking bath having a liquidtemperature of 30° C. (an aqueous solution of boric acid obtained bycompounding 100 parts by weight of water with 3 parts by weight ofpotassium iodide and 3 parts by weight of boric acid) for 30 seconds(cross-linking treatment).

After that, the laminate was uniaxially stretched in its longitudinaldirection (lengthwise direction) between rolls having differentperipheral speeds while being immersed in an aqueous solution of boricacid having a liquid temperature of 70° C. (an aqueous solution obtainedby compounding 100 parts by weight of water with 4 parts by weight ofboric acid and 5 parts by weight of potassium iodide) (underwaterstretching). In this case, the laminate was stretched immediately beforeits rupture (the maximum stretching ratio was 6.0 times).

After that, the laminate was immersed in a washing bath having a liquidtemperature of 30° C. (an aqueous solution obtained by compounding 100parts by weight of water with 4 parts by weight of potassium iodide)(washing treatment).

Subsequently, an aqueous solution of a PVA-based resin (manufactured byThe Nippon Synthetic Chemical Industry Co., Ltd., trade name:“GOHSEFIMER (trademark) Z-200,” resin concentration: 3 wt %) was appliedonto the surface of the PVA-based resin layer of the laminate. Atriacetyl cellulose film having a modulus of elasticity of 4.0 GPa(manufactured by Konica Minolta, Inc., trade name: “KC4UY,” thickness:40 μm) was attached to the resultant, and the whole was heated in anoven maintained at 60° C. for 5 minutes, thereby producing an opticallyfunctional film laminate having a polarizing film with a thickness of 5μm.

The resultant optically functional film laminate was mounted on a flattable so that its resin substrate was on a lower side, and then peelingwas performed in a state where end portions of the PVA-based resin layer(polarizing film) and the triacetyl cellulose film were held at 90° withrespect to the flat table (peel angle β: 90°). Thus, a polarizing platewas obtained.

The polarizing plate had a modulus of elasticity of 6.0 GPa and a radiusof curvature R of 5 mm, and the peeled resin substrate had a modulus ofelasticity of 2.5 GPa and a radius of curvature R of 2 mm.

Example 1-2

A polarizing plate was obtained in the same manner as in Example 1-1except that the peel angle β was changed to 150°.

Example 1-3

A polarizing plate was obtained in the same manner as in Example 1-1except that: a polyethylene-based surface protective film (manufacturedby Sun A. Kaken Co., Ltd., PAC-3, thickness: 30 μm) was attached to asurface of the optically functional film laminate on the triacetylcellulose film side, and such peeling roll (roll diameter: 20 mm) asillustrated in FIG. 5A was brought into abutment with the film; and thepeel angle β was changed to 120°. Continuous peeling of the roll-shapedoptically functional film laminate was able to be performed more stablyby using the peeling roll.

Example 1-4

A polarizing plate was obtained in the same manner as in Example 1-1except that: a polyethylene-based surface protective film (manufacturedby Sun A. Kaken Co., Ltd., PAC-3, thickness: 30 μm) was attached to asurface of the optically functional film laminate on the triacetylcellulose film side, and such peeling bar (diameter of tip portion: 5mm) as illustrated in FIG. 5B was brought into abutment with the film;and the peel angle β was changed to 120°. Continuous peeling of theroll-shaped optically functional film laminate was able to be performedmore stably by using the peeling bar in the same manner as in Example1-3.

Comparative Example 1-1

An optically functional film laminate obtained in the same manner as inExample 1-1 was mounted on a flat table so that its triacetyl cellulosefilm was on a lower side, and then peeling was attempted in a statewhere an end portion of the resin substrate was held at 90° with respectto the flat table (peel angle α:90°).

Comparative Example 1-2

Peeling was attempted in the same manner as in Comparative Example 1-1except that the peel angle α was changed to 150°.

Example 2

A norbornene-based resin film (manufactured by JSR Corporation, tradename: “ARTON,” thickness: 150 μm) having a long shape, a Tg of 130° C.,and a modulus of elasticity of 2 GPa was used as a resin substrate.

An aqueous solution of a polyvinyl alcohol (PVA) resin (manufactured byThe Nippon Synthetic Chemical Industry Co., Ltd., trade name: “GOHSENOL(registered trademark) NH-26”) having a polymerization degree of 2,600and a saponification degree of 99.0 mol % was applied onto one surfaceof the resin substrate, and was then dried at 80° C. so that a PVA-basedresin layer having a thickness of 7 μm was formed, thereby producing alaminate.

The resultant laminate was stretched in its widthwise direction at astretching ratio of up to 4.5 times under heating at 140° C. with atenter apparatus by free-end uniaxial stretching. The thickness of thePVA-based resin layer after the stretching treatment was 3 μm (in-airstretching).

Next, the laminate was immersed in a dyeing bath having a liquidtemperature of 30° C. (an aqueous solution of iodine obtained bycompounding 100 parts by weight of water with 0.5 part by weight ofiodine and 3.5 parts by weight of potassium iodide) for 60 seconds(dyeing treatment).

Next, the laminate was immersed in a cross-linking bath having a liquidtemperature of 60° C. (an aqueous solution of boric acid obtained bycompounding 100 parts by weight of water with 5 parts by weight ofpotassium iodide and 5 parts by weight of boric acid) for 60 seconds(cross-linking treatment).

After that, the laminate was immersed in a washing bath (an aqueoussolution obtained by compounding 100 parts by weight of water with 3parts by weight of potassium iodide), and was then dried with warm airat 60° C. (washing and drying treatments).

Subsequently, an aqueous solution of a PVA-based resin (manufactured byThe Nippon Synthetic Chemical Industry Co., Ltd., trade name:“GOHSEFIMER (trademark) Z-200,” resin concentration: 3 wt %) was appliedonto the surface of the PVA-based resin layer of the laminate. Anorbornene-based resin film having a modulus of elasticity of 2 GPa(manufactured by JSR Corporation, trade name: “ARTON,” thickness: 35 μm)was attached to the resultant, and the whole was heated in an ovenmaintained at 80° C. for 5 minutes, thereby producing an opticallyfunctional film laminate having a polarizing film with a thickness of 3μm.

The resultant optically functional film laminate was mounted on a flattable so that its resin substrate was on a lower side, and then peelingwas performed in a state where end portions of the PVA-based resin layer(polarizing film) and the norbornene-based resin film were held at 90°with respect to the flat table (peel angle β: 90°). Thus, a polarizingplate was obtained.

The polarizing plate had a modulus of elasticity of 5.0 GPa and a radiusof curvature R of 5 mm, and the peeled resin substrate had a modulus ofelasticity of 2.5 GPa and a radius of curvature R of 2 mm.

Comparative Example 2

An optically functional film laminate obtained in the same manner as inExample 2 was mounted on a flat table so that its norbornene-based resinfilm was on a lower side, and then peeling was attempted in a statewhere an end portion of the resin substrate was held at 90° with respectto the flat table (peel angle α:90°).

The polarizing plates obtained in Examples and Comparative Examples wereevaluated for their external appearances by visual observation. Table 1shows the results of the evaluation together with the results of themeasurement of their peel tensions. It should be noted that evaluationcriteria for the external appearances are as described below.

(Evaluation Criteria for External Appearance)

Good: The resin substrate was able to be continuously peeled in alengthwise direction, and neither a wrinkle nor foreign matter (such asa substrate residue) was observed in the resultant polarizing plate.Bad: It was difficult to continuously peeling the resin substrate, and awrinkle or foreign matter occurred in the resultant polarizing plate.

TABLE 1 External Peel Stretching Peel appear- tension Peeling mode angleance (N/15 mm) auxiliary Example 1-1 Underwater β: 90° Good 0.2 —Example 1-2 Underwater β: 150° Good 0.2 — Example 1-3 Underwater β: 120°Good 0.2 Peeling roll Example 1-4 Underwater β: 120° Good 0.2 Peelingbar Comparative Underwater α: 90° Bad 9.0 — Example 1-1 ComparativeUnderwater α: 150° Bad 12.0 — Example 1-2 Example 2 In-air β: 90° Good0.2 — Comparative In-air α: 90° Bad 9.0 — Example 2

The polarizing plate of the present invention is suitably used forliquid crystal panels of, for example, liquid crystal televisions,liquid crystal displays, cellular phones, digital cameras, videocameras, portable game machines, car navigation systems, copyingmachines, printers, facsimile machines, clocks, and microwave ovens. Thepolarizing film of the present invention is also suitably used as anantireflection film for an organic EL device.

Many other modifications will be apparent to and be readily practiced bythose skilled in the art without departing from the scope and spirit ofthe invention. It should therefore be understood that the scope of theappended claims is not intended to be limited by the details of thedescription but should rather be broadly construed.

1.-16. (canceled)
 17. A method of manufacturing a polarizing plate,comprising: forming a laminate having a resin substrate and a polyvinylalcohol-based resin layer formed on one side of the resin substrate;stretching and dyeing the laminate to produce a polarizing film on theresin substrate; laminating an optically functional film on thepolarizing film on the resin substrate to produce an opticallyfunctional film laminate; and peeling the resin substrate from theoptically functional film laminate, wherein the peeling is performed sothat an angle α is smaller than an angle β; wherein the angle α isformed between a surface of the optically functional film laminateimmediately before the peeling and a peeling direction of the resinsubstrate, and wherein the angle β is formed between the surface of theoptically functional film laminate immediately before the peeling and apeeling direction of the polarizing film.
 18. The method ofmanufacturing the polarizing plate according to claim 17, wherein adifference between the angle α and the angle β is 60° or more.
 19. Themethod of manufacturing the polarizing plate according to claim 18,wherein the difference between the angle α and the angle β is 90° to180°.
 20. The method of manufacturing the polarizing plate according toclaim 17, wherein a tension needed for the peeling is 3.0 N/mm or less.21. The method of manufacturing the polarizing plate according to claim17, wherein the resin substrate has a modulus of elasticity at a time ofthe peeling of 2 GPa to 3 GPa.
 22. The method of manufacturing thepolarizing plate according to claim 17, wherein the resin substrate hasa radius of curvature at a time of the peeling of 1 mm to 10 mm.
 23. Themethod of manufacturing the polarizing plate according to claim 17,wherein, in the peeling, a peeling roll is arranged on the opticallyfunctional film laminate on an optically functional film side, and thepeeling is performed with an aid of the peeling roll.
 24. The method ofmanufacturing the polarizing plate according to claim 23, wherein thepeeling roll has a diameter of 10 mm to 30 mm.
 25. The method ofmanufacturing the polarizing plate according to claim 17, wherein, inthe peeling, a peeling bar is arranged on the optically functional filmlaminate on an optically functional film side, and the peeling isperformed with an aid of the peeling bar.
 26. The method ofmanufacturing the polarizing plate according to claim 25, wherein thepeeling bar has a diameter of a tip portion of 5 mm to 30 mm.
 27. Themethod of manufacturing the polarizing plate according to claim 23,wherein a surface of the optically functional film laminate on theoptically functional film side has a surface protective film attachedthereto.
 28. The method of manufacturing the polarizing plate accordingto claim 25, wherein a surface of the optically functional film laminateon the optically functional film side has a surface protective filmattached thereto.